1. Field of the Invention
This invention relates to methods of controlling fungus of the genus Fusarium particularly Fusarium oxysporum f. lycopersici with bis(aryl)methyl alkyl sulfones, particularly bis(4-chlorophenyl)methyl methyl sulfone.
2. Description of the Prior Art
Because fungi cause harmful effects, such as diseases, which affect crop and ornamental plants, chemical compounds are required to control these harmful effects by preventing or eradicating them. The action of a chemical towards a specific fungus is not a priori predictable, because of very complicated biochemical reactions. For example, a compound may act as a respiratory enzyme which causes respiratory malfunction in the attacking fungus, or as a growth hormone which stimulates a rapid growth causing the fungus to die, or as a metabolite within the plant which stimulates the plant to fight off the disease or to kill the fungus.
Fungi of the genus Fusarium, particularly the species Fusarium oxysporum f. lycopersici, harmfully affects plants, such as tomato plants, with a wilt disease called Fusarium Wilt of Tomatoes. These are fungi which need to be controlled. Although certain sulfides, sulfoxides, and sulfones possess biochemical activity against certain organisms, as shown in the following prior art; nothing therein suggests controlling the harmful effects of Fusarium fungi with bis(4-chlorophenyl)methyl methyl sulfone.
For example, bis(4-chlorophenyl)methyl methyl sulfide is active against the mosquito species, Anopheles albimanus, as described by R. L. Metcalf et al, Bulletin of the World Health Organization, Vol. 38, pages 633-647, (1968). Phenylmercaptomethane sulfonamide is described as being active against Phytophthora infestans (U.S. Pat. No. 3,412,149). Oximidomethane sulfonamides are disclosed as being active against bacteria and weeds (U.S. Pat. No. 3,549,702). 4-Methoxyphenyl diiodomethyl sulfone is shown to inhibit the growth of Aspergillus oryzae (U.S. Pat. No. 3,615,745), and 2,4,5,4'-tetrachlorodiphenyl sulfide, sulfoxide, and sulfones are shown to be effective against Red Spider Mites (U.S. Pat. No. 3,054,719). Other sulfones, sulfides, and sulfoxides are described but their activity against fungus are not known. For example, certain aryl sulfoxides are described by C. Shunk el al (U.S. Pat. No. 3,466,377), of the type B--X--C(Ar) (Ar')--SO.sub.2 --R wherein B is a lower aliphatic tertiary-amino group, X is a lower alkylene group, Ar and Ar' are aryl groups, and R is an alkyl group, as analgetics. 4,4'-Chlorodiphenyl sulfone is claimed as an important monomer for preparing polyarylene polyethers (U.S. 3,415,887). Other aryl sulfones are described as both analgetics and anti-pyretics by C. Shunk et al (U.S. Pat. No. 3,637,803 and U.S. Pat. No. 3,689,567); Jean A. Gautier et al in U.S. Pat. No. 3,624,094 describes alpha-[(phenyl sulfinyl) methyl]-alpha phenyl derivatives of pyridinemethanols as analgetics and anti-inflammatory agents.